A/T - Clicking/Whine in Third/Fourth Gear

Bulletin: 93-74L60-5

Date: June '93

Ref.No.: 93-155-74L60

Corp.Ref.No.: 277121R

SUBJECT:
CLICK/WHINE IN THIRD/FOURTH GEAR (INSTALL NEW LOW AND REVERSE CLUTCH FIBER PLATES)

MODELS AFFECTED:
1991-93 ROADMASTERS

THIS BULLETIN IS BEING REVISED TO ADD THE 1993 MODEL YEAR, ADD THE "NOTE" IN CORRECTION SECTION AND CHANGE THE SERVICE PARTS INFORMATION. PLEASE DISCARD BULLETIN 92-74L60-6.

CONDITION:

Some 1991-93 vehicles with HYDRA-MATIC 4L60 transmissions built before November 19, 1992 (Julian Date 324) may exhibit a clicking or whining noise in third and fourth gear. A customer may also describe it as a ticking or rattle noise.

CAUSE:

The clicking noise is caused by transmission fluid passing over the friction plates of the low and reverse clutch. The fluid causes them to vibrate when the low and reverse clutch is not applied (third and fourth gear).

CORRECTION:





Install five new fiber plates in the low and reverse clutch. The new plates have a non-groove configuration.

NOTE:
All HYDRA-MATIC 4L60 transmissions built on or after November 19, 1992 (Julian Date 324) have been assembled with the new low and reverse clutch fiber plates.

SERVICE PARTS INFORMATION:

Description Part Number Transmission

Plate Asm.,-Low and Reverse Clutch 8684089 4L60

Package-Overhaul Repair Complete 8689951 4L60

Parts are expected to be available on 6/07/93.